This invention relates to a tool such as a level, and more particularly to a removable end cap feature for a level.
A level generally includes at least one bubble vial secured to an elongate frame. The frame may be constructed of metal, plastic, organic material (e.g., wood), or other rigid material, and has a cross section that may vary between and within models, but commonly is in the form of either a box beam having a generally rectangular cross-section or an I-beam having an I-shaped cross-section. Alternatively, the frame may have other forms suitable for specific applications (e.g., an angular frame for leveling pictures or posts). The bubble vial indicates the orientation of the level, e.g., relative to a horizontal, vertical, or a diagonal plane. The vial contains a quantity of fluid and a bubble, and the user views the position of the bubble within the vial to ascertain the position of the tool relative to the desired plane. A level may also include other satisfactory means for indicating the orientation of the level relative to a plane, such as an electronic indicator or the like.
A level typically has end caps secured to the end of the frame, which serve to protect the ends of the level since the level may be subjected to rough operating and storage conditions, e.g., on a construction site. One drawback of level end caps is that they prevent the level gauging surface from reaching all the way to a wall that defines a corner, which is disadvantageous when it is desired to use the gauging surface to draw a line all the way into the corner.
It is therefore an object of the present invention to provide an end cap for a level that can be fastened to and removed from the frame by a user simply and quickly and without the use of additional materials and special tools, and without removing any pieces and parts from the level or the end cap.
In accordance with one aspect of the invention, a tool such as a level includes an elongate frame with two ends. The frame defines at least one gauging surface, and has a cross section that may vary between embodiments and may also vary along the length of the frame. As noted previously, common cross sections typically include a box beam cross section and an I-beam cross section. Embodiments with a box beam cross section have a frame with spaced-apart first and second walls, both of which may extend substantially parallel to each other along the elongate axis of the frame and at an angle relative to the gauging surface. Rather than first and second walls, embodiments with an I-beam cross section have a web that extends between an upper flange and lower a flange along the longitudinal axis of the frame and at an angle relative to the gauging surface.
One or more recesses extend through the frame near each end. The one or more recesses generally lie in a plane that contains one of the first and second walls (e.g., in the case of box beam embodiments) or the web (e.g., in the case of I beam embodiments). The one or more recesses are sized to receive a sliding retainer carried by the end cap, which is movable between an engaged position that selectively secures the end cap to the frame, and a release position that selectively enables the end cap to be removed from the frame. At least one of the recesses includes capture protrusions that are engaged by the retainer when in the engaged position to prevent disengagement of the end cap, as more fully described below.
The one or more capture protrusions, which may be defined by one or more indentations associated with the recess, are configured to engage the sliding retainer when the sliding retainer is in the engaged position in order to prevent removal of the end cap from the frame. When the sliding retainer is moved to the release position within an opening defined by the end cap, clearance structure on the sliding retainer is positioned in alignment with the one or more capture protrusions such that the end cap can be moved past the capture protrusions and removed from the frame by application of an axial outward force on the end cap. The end cap can subsequently be secured to the end cap by moving the sliding retainer to the release position and applying an axial inward force on the end cap, which enables the clearance structure on the end cap to move past the one or more capture protrusions. The sliding retainer is then returned to the engaged position to releasably secure the end cap to the end of the frame.
The end cap includes a main cap body and the sliding retainer. The main cap body may be constructed of any single material or combination of rugged materials, such as a rubber or plastic capable of absorbing impacts and limiting energy transfer to other components. Furthermore, the main cap body may be constructed as a single part or an assembly of sub-parts, and may be fully or partially hollow to conserve materials usage and cost, reduce weight, or to provide functional interior surfaces that cooperate with other structure, such as the sliding retainer.
The main cap body includes an inner portion that overlaps the end portion of the frame and an outer portion that projects outwardly from the end of the frame. In one embodiment, the main cap body includes a shoulder that fixes the position of the main cap body relative to the frame.
The outer portion of the main cap body may have any number of geometries and shapes, and representatively may have a shape that allows the entire level assembly to lie flat on any of its elongate sides. The outer portion may also feature apertures (e.g., to facilitate carrying or hanging the level on a hook), recesses, textures (e.g., to facilitate gripping), or other useful characteristics.
The sliding retainer is movably positioned within the opening of the end cap, and generally has an engaged position and a release position, as noted previously. When the end cap is engaged with the frame and the sliding retainer is in the engaged position, the end cap may not be disengaged from the frame. Conversely, when the end cap is engaged with the frame and the sliding retainer is in the release position, the end cap may be removed from the frame.
For ease of assembly, the sliding retainer may be in the form of a pair of retainer subsections that are positioned within the opening from opposite sides defined by the end cap, and which are configured for engagement with each other to so as to form the sliding retainer.
The sliding retainer may include a biasing mechanism to urge it toward the engaged position, which facilitates operation and also prevents inadvertent movement of the sliding retainer to the release position that could result in the unintentional disengagement of the end cap. The biasing mechanism may be any satisfactory configuration, and in one embodiment may be in the form of a spring interposed between the sliding retainer and the main cap body that urges the sliding retainer toward the engaged position.
Various other features, objects and advantages of the invention will be made apparent from the following description taken together with the drawings. Although the removable end cap assembly is described in the context of a level, it should be understood that it could also perform a useful function in other applications, such as squares, straight edges, in relation to handles (e.g., on tools), in relation to posts or poles (e.g., in shelving assemblies), and other applications not specifically mentioned herein.
In describing the embodiments of the invention which are illustrated in the drawings, specific terminology will be resorted to for the sake of clarity. However, it is not intended that the invention be limited to the specific terms so selected and it is to be understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar purpose. For example, the words connected, attached, or terms similar thereto are often used. They are not limited to direct connection but include connection through other elements where such connection is recognized as being equivalent by those skilled in the art.